Electrical ignition system



F. CONRAD.

ELECTRICAL IGNITION SYSTEM. APPLICATION FILED SEPT. 26, I9I0- RENEWEDAPR- 4,191?- 1,352,433. I PatentedSept. 14, 1920.

z'f zz WITNESSES:

. y Z INVENTOR primary circuit that FRANK CONRAD,

OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOIISE ELECTRIC ANDMANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VAN IA.

ELECTRICAL IGNITION SYSTEM.

Application filed September 26, 1910, Serial No. 583,858. Renewed April4, 1917.

To all whom it may concern.

Be it known that I, FRANK CONRAD, a citizen of the United States, and aresident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in ElectricalIgnition Systems, of which the following is a specification.

My invention relates to electrical ignition systems and particularly tosuch systems as are employed for igniting the charges of explosionengines and for similar purposes.

The object of my invention is to provide a system of the characterindicated, in which a high potential is produced for causing the initialdischarge across the gap between the terminals of the spark plug and inwhich a relatively large amount of energy is caused to follow the saiddischarge. The system is simple and inexpensive and permits of theemployment of its source of current for lighting and for other purposes.

.Figure 1 of the accompanying drawing illustrates, diagramatically, asystem embodying my invention, and Fig. 2 illustrates a modification ofthe system.

As shown, the system is supplied with current from a battery 1, whichmay be either a primary or a secondary battery, though it may besupplied from any other suitable source, such as a generator or magneto.If desired, the source may also supply current for lighting or otherpurposes.

Directly connected to the battery, is a comprises a coil 2 of areactance device 2 an interrupter 3 and a primary winding 4 of atransformer or induction coil 5, the said devices being all connected inseries relation. The interrupter 3 may conveniently consist of an arm 6that is normally maintained in engagement with a terminal member 7 andis raised out of engagement therewith by means of a cam 8, that isactuated by the engine or other device in connection with which theignition system is employed.

In shunt to the interrupter, is a condenser 10 that is employed, asusual, for the purpose of assisting the interrupter to quickly breakcircuit, and, in shunt to the ini the primary terrupter and the primarywinding 4 of the induction coil, isv another condenser 11, in whichenergy is temporarily stored, upon interruption of the primary circuit vIn shunt to the secondary winding 12 of circuit of the system,

device 2 is Serial No. 159,844.

the induction coil 5, is an auxiliary spark device 13 having permanentlyseparated terminals, the distance between which is so adjusted that,when the primary circuit is interrupted, the high voltage induced in thesecondary circuit will cause a discharge between them, thereby settingup high voltage. The secondary, circuit further comprises a spark plug14 that is connected between the terminals of the secondary winding 12and those of the auxiliary spark device- 13, condensers 15 and 16 beingrespectively included in the connections between said parts for thepurpose of preventing the supply of direct current to the parts 12 and13, and also to cause an accumulation of the potential in the secondarycircuit. The spark plug 14 is also connected, independently of itsconnections to the secondary circuit, to the terminals of the reactancecoil 2 that is in the primary circuit and, in some instances, it may befound desirable to include, in the said connections, other coils 17 and18 that are wound upon the same core as the coil 2 and serve to increasethe potential, and to reduce the current, of the energy supplied to thespark plug 14 from the primary circuit,

the periods of the discharge between the terminals'of the spark plugbeing thereby increased.

WVhen the terminals of the interrupter 8 engage each other, the batteryor source 1 supplies current to the primary winding 4 of the inductioncoil, energy being at the same time stored in the reactancedevice 2.Upon interruption of-"the primary circuit by the interrupter 3, thecondenser 11 becomes charged, and a high potential is induced in thesecondary winding 12 of the induction coil which causes a discharge,between the terminals of the auxiliary spark device 13, the dischargesetting up high-potential and high-frequency oscillations in thesecondary which are conducted to the spark plug 14 through thecondensers 15 and 16 and which, by reason of their high voltage andfrequency, readily ump the gap between its terminals. The highresistance of the gap between the terminals of the spark plug being thusbroken down, the energy previously stored in the reactance alsodischarged across the gap followed by the rebound of the charge put intothe condenser 11 upon interruption of the primary circuit. A veryreliable and Specification of Letters Patent... Patented S t 14 1920 rhot spark is thus produced which is particularly effective for ignitionpurposes. Since the voltage necessary to overcome the resistance of thegap between the terminals of the spark plug remains substantiallyuniform, the time required to discharge the energy stored in thereactance device 2 across the said gap will depend upon the number ofturns in the coils of said device. It will be noted that the energystored in device 2 is discharged through all of the coils 2, 17 and 18thereof, and, consequently, a greater time is required to complete thedischarge than if the discharge occurred only through the coil 2. Thisinsures that the spark between the terminals of the spark plug willcontinue a sufiicient length of time to be effective. The discharge ofthe stored energy through all of the coils 2, 17 and 18 insures that itwill be supplied to the spark plug at a voltage higher than that of thesource, the reactance device operating, in effect, as an autotransformersince the coil 2 is common to the primary and the secondary circuits.

It will thus be seen that, by means of the present system, ahigh-potential discharge is first produced which causes a breaking downof the resistance of the gap between the terminals of the spark plug,and that thisis followed by a discharge of energy obtained from theprimary circuit, which energy is in such form as to produce a spark thatis particularly suitable for ignition and similar purposes.

In the system of Fig. 2, the circuits are somewhat simplified andrearranged, the same reference numerals bein applied to partscorresponding to those found in the system of Fig. 1. One terminal ofthe battery 1, the condenser 11, the interrupter 3, the spark plug 14.-and the secondary circuit is grounded, the wiring being. thussimplified. The coil 20 of a reactance device 21 is connected in serieswith the battery 1 and the spark plug 1 1, between .their ungroundedterminals, and one terminal of primary winding 4 of the induction coilis connected to approximately the middle or another suitableintermediatepoint 22 of the coil 20.

ne terminal of the condenser 11 is connected to the coils 20 at 23between the connection of the winding 4 thereto and the terminal thereofthat is plug 14. Only one condenser 15 is used in the secondary circuitof the induction coil.

he primary circuit that is periodically interrupted by the interrupter 3comprises the battery 1, the left-hand portion of the coil 20, thewinding 4, and the interrupter When this circuit is interrupted,high-voltage and high-fre uency oscillations are set up in the secon arycircuit which jump across the gap of the spark plug, followed by thedischarge of the energy stored in the ing a source of electricity,

the condenser 11,

spark device and a spark plug, the spark plug being also in circuit withthe reactance device.

2. An electrical ignition system comprising a source of electricity, aprimary circuit associated with said sourceand including an interrupterand a reactance device, and a secondary circuit inductively related tothe primary circuit and including an auxiliary spark device, a sparkplug, and condensers interposed between the spark plug and the auxiliaryspark device, the spark plug being also in circuit with the reactancedevice.

3. An electrical ignition I a primary circuit associated with saidsource and including an interrupter and a reactance device, and asecondary circuit inductively related to the primary circuit andincluding an auxiliary spark device and a spark plug, the spark plugbeing also in circuit with the reactance device, and reactance includedin the connections of the spark plug to the reactance ing systemcomprise a source of electricity, an induction 0011 having a primary anda secondary winding, the primary winding of which is connected aninterrupter included in circuit with the primary winding of theinduction coil, a condenser connected in parallel to the ininductioncoil, and a spark between the terminals of winding of the induction plugconnected the secondar coil and system compristo the source, a reactancedevice and.

between the terminals of the reactance device.

6. An electrical ignition system comprising a source of electricity, aninduction coil having a primary and a secondary winding, the primarywinding of which is connected to the source, a reactance device and aninterrupter included in circuit with the primary winding of theinduction coil, an auxiliary spark device connected'in circuit with thesecondary winding of the induction coil, a spark plug connected betweenthe terminals of the secondary winding of the induction coil and also tothe reactance device,.and condensers included in the connections betweenthe spark plug and the secondary winding of the induction coil.

7. An electrical ignition system comprising a source of electricity, aninduction coil having a primary and a secondary winding, the primarywinding of which is connected to the source, a reactance device and aninterrupter included in circuit with the primary winding of theinduction coil, an auxiliary spark device connected in circuit with thesecondary winding of the induction coil, a spark plug connected betweenthe terminals of the secondary winding of the induction coil and also tothe reactance device, and reactance coils included in the connectionsbetween the spark plug and the reactance device.

8. An electrical ignition system comprising a source of electricity, aprimary circuit associated with said source and including an interrupterand a reactance device, and a secondary circuit inductively related tothe primary circuit and including a spark plug that is also connectedbetween terminals of the reactance device.

9. An electrical ignition system comprising a source of electricity, aprimary circuit associated with said source and including an interrupterand a portion of the wind ing of a reactance device, and a secondarycircuit inductively related to the primary circuit and including a sparkplug and between the terminals of which the total winding of thereactance device is connected.

10. An electrical ignition system comprising a source of electricity, areactance device having a plurality of coils, an interrupter, a primarycircuit including the source, one of the coils of the reactance device,and the interrupter, a secondary circuit that is inductively related tothe primary circuit, and a spark plug included in the secondary circuitand connected to all of the coils of the reactance device.

11. An electrical ignition system comprising a source of electricity, aninduction coil having a primary and a secondary winding, the primarywinding of which is connected to the source, a reactance device and aninterrupter connected in circuit with the primary winding of theinduction 0011, a condenser connected in parallel with the interrupterand the primary winding of the induction coil, an auxiliary spark deviceconnected to the secondary winding of the induction coil, and a sparkplug connected between the terminals of the secondary winding of theinduction coil and also between the terminals of the reactance device.

12. An electrical ignition system comprising a source of electricity, aninduction coil having a primary and a secondary winding, the primarywinding of which is connected to the source, a reactance device and aninterrupter included in circuit with the primary winding of theinduction coil, a condenser connected in parallel with the in terrupterand the primary winding of the induction coil, an auxiliary spark deviceconnected in circuit with the secondary winding of the induction coil, aspark plug connected between the terminals of the secondary winding ofthe induction coil and also to the reactance device, and condensersincluded in the connections between the spark plug and the secondarywinding of the induction coil.

13. An electrical ignition system comprising a source of electricity, aninduction coil having a primary and a secondary winding, the primarywinding of which is connected to the source, a reactance device and aninterrupter included in circuit with the primary winding of theinduction coil a condenser connected in parallel with the interrupterand the primary winding of the induction coil, an auxiliary spark deviceconnected. in circuit with the secondary winding of the induction coil,a spark plug connected between the terminals of the secondary winding ofthe induction coil and also to the reactance device, and reactance coilsincluded in the connections between the spark plug and the reactancedevice.

14:. An ignition system comprising a source of current, a spark plug,means receiving current from said source for producing an oscillatorydischarge to initially establish a spark at the spark plug, and energystoring means that receives energy from said source and supplies it tothe spark plug following the initially established spark.

15. An ignition system comprising a source of current, a spark plug,means receiving current from said source for producing an oscillatorydischarge to initially establish a spark at the spark plug, and energystoring means that receives energy from said source and supplies it atan increased voltage to the spark plug following the initiallyestablished spark.

' lish a spark 16. An ignition system comprising a source of current, aspark plug, means receiving current from said source for producing anoscillatory discharge to initially establish a spark at the spark plug,and energy storing means that intermittently receives energy from saidsource and supplies it to the spark plug following the initiallyestablished spark."

17. An ignition system comprising a source of current, a spark plug,means receiving current from said source for producing an oscillatorydischarge to initially establish a spark at the spark plug, and energystoring means that intermittently receives energy from said source andsupplies it at an increased voltage to the spark plug following theinitially established spark.

18. An ignition system comprising a source of energy and a spark plug,of means comprising said source for initially establishing a sparkacross the terminals of said spark plug and means for storing energyreceived from said source and supplying it to said spark plug at avoltage higher than that of said source.

19. An ignition system comprising a source of energy and a spark plug,of means comprising said source for initially establishing a spark atthe spark plug, and means comprising an impedance device for storingenergy received from said source and supplying it to said spark plug ata voltage higher than that of source.

11 ignition system comprising a source of current, and a spark plug, ofmeans comprising said source for producing an oscillatory discharge toinitially estabat the spark plug, and means comprising an impedancedevice for storing energy received from said source and suplishing aspark across the terminals of said spark plug and means for storingenergy received from said source and supplying it to said spark plug.

22. An ignition source of energy and a spark plug, of means comprisingsaid source for initially establishing a spark at the spark plug, andmeans comprising an impedance device for storing energy received fromsaid source and supplying it to said spark plug.

23. An ignition system comprising a source of current and a spark plug,of means comprising said source for initially establishing a sparkacross the terminals of said spark plug, and means in addition to saidsource for storing energy received from said source and supplying itdirectly to said spark plug. 24. In an ignition system, the combinationwith a source-of electricity and a spark plug, of a primary circuitincluding said source, a primary Winding and an interrupter in seriesrelation, a secondary circuit including said spark ondary Windinginductively related to said primary winding, and means for storingelectricityreceived from said source and supplying it to said sparkplug.

In testimony whereof, I have hereunto subscribed my name this 23rd dayof Sept,

FRANIQCONRAD. Witnesses A. W. Corner, B. B. HINES.

system comprising a plug and a sec-.

